837 research outputs found
Parasite specific energy in human filariasis; insights after analysis of parasite antigen-driven lymphokine production
The antigen-specific immune unresponsiveness seen in bancroftian
filariasis was studied by examining lymphokine production
in peripheral blood mononuclear cells (PBMC) or PBMC subpopulations
from 10 patients with asymptomatic microfilaremia,
13 patients with elephantiasis and 6 normal North Americans.
In each group of patients, the kinetics of the lymphokine response
and the response to mitogens and nonparasite antigens
did not differ significantly. In marked contrast, when antigeninduced
lymphokine production was examined, most patients with
microfilaremia were unable to produce either interleukin 2 (IL-
2) or y-interferon (i.e., were nonresponders), and the few who
could (hyporesponders, generally with quite low microfilaremia
levels) did so at levels significantly less than those of patients
with elephantiasis, all of whom showed strong responses to parasite
antigen. Removal of neither adherent cells or T8+ cells
affected the parasite-specific anergy seen in those with microfilaremia,
suggesting a state of T cell tolerance to the parasite in
patients with this most common clinical manifestation of bancroftian
filariasis
Identification of circulating parasite antigen in patients with bancroftian filariasis
Because many cases of lymphatic filariasis cannot be diagnosed either clinically or by
immunodiagnostic test based on antibody detection, recent efforts have been more
directed towards developing methods for detecting parasite antigen in the blood or urine.
Using a solid phase (Sepharose 4B) two-site immunoradiometric assay (IRMA)
employing hyperimmune rabbit antifilarial antisera, we have previously shown (Hamilton
et al., 1984) that essentially all cases ofpatent (ie. microfilaremic) infection in patients with
bancroftian filariasis can be detected by this semi-quantitative assay as well as some
individuals with amicrofilaremic (i.e., 'cryptic') infection. The present communication
reports the results of studies that identify a prominent circulating antigen detected by this
IRMA in sera from patients with microfilaremia. The antigen was eluted from Sepharosebound
rabbit polyclonal antiserum that had been reacted with known antigen positive
sera. It was run in SDS-PAGE, blotted to nitrocellulose paper and identified autoradiographically
using '25l-labelled rabbit antifilarial antiserum. Its high molecular weight
(- 200 kD), stability to acid and boiling, and sensitivity to pronase and periodate suggest
its being a glycoprotein. Isolation of this antigen will permit the development of specific
reagents (such as monoclonal antibodies) which should enhance both the sensitivity and
utility of the currently available antigen detection systems
Ultracoherence and Canonical Transformations
The (in)finite dimensional symplectic group of homogeneous canonical
transformations is represented on the bosonic Fock space by the action of the
group on the ultracoherent vectors, which are generalizations of the coherent
states.Comment: 24 page
Disentangling hindgut metabolism in the American cockroach through single-cell genomics and metatranscriptomics
Omnivorous cockroaches host a complex hindgut microbiota comprised of insect-specific lineages related to those found in mammalian omnivores. Many of these organisms have few cultured representatives, thereby limiting our ability to infer the functional capabilities of these microbes. Here we present a unique reference set of 96 high-quality single cell-amplified genomes (SAGs) from bacterial and archaeal cockroach gut symbionts. We additionally generated cockroach hindgut metagenomic and metatranscriptomic sequence libraries and mapped them to our SAGs. By combining these datasets, we are able to perform an in-depth phylogenetic and functional analysis to evaluate the abundance and activities of the taxa in vivo. Recovered lineages include key genera within Bacteroidota, including polysaccharide-degrading taxa from the genera Bacteroides, Dysgonomonas, and Parabacteroides, as well as a group of unclassified insect-associated Bacteroidales. We also recovered a phylogenetically diverse set of Firmicutes exhibiting a wide range of metabolic capabilities, including—but not limited to—polysaccharide and polypeptide degradation. Other functional groups exhibiting high relative activity in the metatranscriptomic dataset include multiple putative sulfate reducers belonging to families in the Desulfobacterota phylum and two groups of methanogenic archaea. Together, this work provides a valuable reference set with new insights into the functional specializations of insect gut symbionts and frames future studies of cockroach hindgut metabolism
Applications of Canonical Transformations
Canonical transformations are defined and discussed along with the
exponential, the coherent and the ultracoherent vectors. It is shown that the
single-mode and the -mode squeezing operators are elements of the group of
canonical transformations. An application of canonical transformations is made,
in the context of open quantum systems, by studying the effect of squeezing of
the bath on the decoherence properties of the system. Two cases are analyzed.
In the first case the bath consists of a massless bosonic field with the bath
reference states being the squeezed vacuum states and squeezed thermal states
while in the second case a system consisting of a harmonic oscillator
interacting with a bath of harmonic oscillators is analyzed with the bath being
initially in a squeezed thermal state.Comment: 14 page
A persistent Norwegian Atlantic Current through the Pleistocene glacials
Changes in ocean‐circulation regimes in the northern North Atlantic and the Nordic Seas may affect not only the Arctic but potentially hemispheric or even global climate. Therefore, unraveling the long‐term evolution of the North Atlantic Current‐Norwegian Atlantic Current system through the Pleistocene glaciations could yield useful information and climatological context for understanding contemporary changes. In this work, ~50,000 km2 of 3‐D seismic reflection data are used to investigate the Pleistocene stratigraphy for evidence of paleo‐oceanographic regimes on the mid‐Norwegian margin since 2.58 Ma. Across 33 semicontinuous regional paleo‐seafloor surfaces ~17,500 iceberg scours have been mapped. This mapping greatly expands our spatiotemporal understanding of currents and iceberg presence in the eastern Nordic Seas. The scours display a dominant southwest‐northeast trend that complements previous sedimentological and numerical modeling studies that suggest northward‐flowing currents in the Norwegian Sea during the Pleistocene. This paleo‐oceanographic study suggests that through many of the Pleistocene glaciations, the location of surface ocean currents in the Norwegian Sea and, by extension, the eastern North Atlantic, were broadly similar to the present
Lessons from the Pacific programme to eliminate lymphatic filariasis: a case study of 5 countries
Lymphatic Filariasis (LF) is an important Neglected Tropical Disease, being a major cause of disability worldwide. The Global Programme to Eliminate Lymphatic Filariasis aims to eliminate LF as a public health problem by the year 2020, primarily through repeated Mass Drug Administration (MDA). The Pacific region programme commenced in 1999. By June 2007, five of the eleven countries classified as endemic had completed five MDA campaigns and post-MDA prevalence surveys to assess their progress. We review available programme data and discuss their implications for other LF elimination programs in developing countries. Reported MDA coverage and results from initial surveys and post-MDA surveys of LF using the immunochromatographic test (ICT) from these five Pacific Island countries (Tonga, Niue, Vanuatu, Samoa and Cook Islands) were analysed to provide an understanding of their quality and programme progress towards LF elimination. Denominator data reported by each country programme for 2001 was compared to official sources to assess the accuracy of MDA coverage data. Initial survey results from these five countries revealed an ICT prevalence of between 2.7 and 8.6 percent in individuals tested prior to commencement of the programme. Country MDA coverage results varied depending on the source of denominator data. Of the five countries in this case study, three countries (Tonga, Niue and Vanuatu) reached the target prevalence of <1% antigenaemia following five rounds of MDA. However, endpoint data could not be reliably compared to baseline data as survey methodology varied. It was concluded that accurate and representative baseline and post-campaign prevalence data is crucial for determining program effectiveness and the factors contributing to effectiveness. This is emphasised by the findings of this case study. While three of the five Pacific countries reported achieving the target prevalence of <1% antigenaemia, limitations in the data preclude identification of key determinants of this achievement
Optimism for lymphatic filariasis elimination:a case study of Tandahimba district, Southern Tanzania
Centralised and Distributed Optimization for Aggregated Flexibility Services Provision
The recent deployment of distributed battery units in prosumer premises offer
new opportunities for providing aggregated flexibility services to both
distribution system operators and balance responsible parties. The optimization
problem presented in this paper is formulated with an objective of cost
minimization which includes energy and battery degradation cost to provide
flexibility services. A decomposed solution approach with the alternating
direction method of multipliers (ADMM) is used instead of commonly adopted
centralised optimization to reduce the computational burden and time, and then
reduce scalability limitations. In this work we apply a modified version of
ADMM that includes two new features with respect to the original algorithm:
first, the primal variables are updated concurrently, which reduces
significantly the computational cost when we have a large number of involved
prosumers; second, it includes a regularization term named Proximal Jacobian
(PJ) that ensures the stability of the solution. A case study is presented for
optimal battery operation of 100 prosumer sites with real-life data. The
proposed method finds a solution which is equivalent to the centralised
optimization problem and is computed between 5 and 12 times faster. Thus,
aggregators or large-scale energy communities can use this scalable algorithm
to provide flexibility services.Comment: 10 pages, 7 figure
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